Critical fields and the critical current density of La/sub 1. 85/Sr/sub 0. 15/CuO/sub 4/

Journal Article · Tue Sep 01 04:00:00 EDT 1987 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.36.4003· OSTI ID:6292373

Senoussi, S; Oussena, M; Ribault, M; Collin, G

A detailed investigation of the magnetic and transport properties of La/sub 1.85/Sr/sub 0.15/CuO/sub 4/ in the superconducting state is presented. It is concluded that the magnetic and transport behavior is that of a granular type-II superconductor in which strongly superconducting grains are coupled via weak superconducting links. Five characteristic fields are identified. H/sub c//sub 1//sup w/ (approx. =1 Oe at 4 K) is the field at which the first vortex line penetrates the weak links. At H = H/sup w/ (approx. =11 Oe at 4.2 K) the London penetration depth in the weak links is very large compared to their dimensions. H/sub c//sub 1//sup g/ (approx. =300 Oe at 4.2 K) defines the first flux thread entering the grains themselves. H/sup g/ is the value above which the magnetic behavior of the grain is thought to be governed by Abrikosov's negative surface energy model. The critical current density measured by the resistivity technique is about 8 A cm/sup 2/ and is imposed by the sample size and compositional inhomogeneities and by H/sub c//sub 1//sup w/, whereas the bulk (or intragrain) critical density could attain 10/sup 5/--10/sup 6/ A/cm/sup 2/.

• Research Organization: Laboratoire de Physique des Solides, Centre d'Orsay, Universite de Paris-Sud, Batiment 510, 91405 Orsay Cedex, France
• OSTI ID: 6292373
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 36:7; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
CRITICAL CURRENT
CRITICAL FIELD
CURRENT DENSITY
CURRENTS
DATA
ELECTRIC CONDUCTIVITY
ELECTRIC CURRENTS
ELECTRICAL PROPERTIES
EXPERIMENTAL DATA
GRANULAR MATERIALS
INFORMATION
LANTHANUM COMPOUNDS
LANTHANUM OXIDES
MAGNETIC FIELDS
MAGNETIZATION
MATERIALS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PENETRATION DEPTH
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
STRONTIUM COMPOUNDS
STRONTIUM OXIDES
SUPERCONDUCTIVITY
TRANSITION ELEMENT COMPOUNDS